1. Field of the Invention
The present invention relates to a TV, and more particularly, to a device and method for displaying additional information to a TV program.
2. Background of the Related Art
Generally, an audio/video signal transmitted to a TV also includes additional information data. Particularly, the additional information data, such as a weekly broadcasting guide information, is provided to better serve the viewers. Therefore, a TV receiver requires a demultiplexer, by which a received signal is separated into a video signal, an audio signal; and additional information data. Namely, the demultiplexer separates either a Transport Stream (TS) or a Program Stream (PS) which includes a plurality of elementary data streams such as the video, audio and other additional information combined by a broadcasting station for storage or for transmission of data.
Thus, the additional information may be displayed on a TV screen with or separately from a broadcasted image by an Electronic Program Guide (EPG). Particularly, the EPG contains basic TV guides for program times and channels as well as detail information such plots, the type of program, whether the program is pay TV, or other available services. Thus, viewers can obtain information about present and future TV programs directly from a TV screen, without the need of other guide mediums such as a newspaper. As the number of channels and programs increase, the EPG provides a more convenient tool in searching for and/or viewing a program.
FIG. 1 is a block diagram of a typical digital TV receiving and displaying program guide information. The digital TV includes a remote control 101 which allows viewers or users to control the TV by radio signals; a remote receiver 102 which receives signals output by the remote control 101 and outputs a key code value corresponding to a key input by the user through the remote control 101; a tuner 103 which tunes frequency corresponding to a desired channel among the signals received through an antenna or a cable; a demodulator 104 which demodulates the tuned channel frequency by a reversed modulation; a demultiplexer 105 which demultiplexes and separates the demodulated signal into an audio/video signals and additional guide information data; an audio/video decoder 106 which decodes the audio/video signal separated by the demultiplexer 105; a display unit 107 which displays the decoded signal; a storage 108 which stores the program guide information data separated by the demultiplexer 105; a controller 109 which controls the tuner 103, the demodulator 104, the demultiplexer 105, the storing and the displaying of the program guide information data, in accordance with the signal from the remote receiver 102; and a memory 110 which temporarily stores the data from the storage 108 in accordance with the control of the controller 109.
To operate the digital TV receiver, a user selects program channels transmitted through an antenna or a cable using the remote control 101 such as by pressing keys. The remote receiver 102 then outputs to the controller 109 a key code value corresponding to the key input from the remote control 101. The controller 109 outputs a control signal for tuning a desired channel frequency in accordance with the key code value of the remote receiver 102. Additionally, the controller 109 respectively outputs control signals to the demodulator 104 and the demultiplexer 105, for demodulating the tuned signal and for demultiplexing the demodulated signal.
The tuner 103 tunes a selected channel frequency among the signals received through an antenna or a cable in accordance with the control signal of the controller 109, and outputs the tuned channel frequency to the demodulator 104. The demodulator 104 demodulates the tuned channel frequency under the control of the controller 109. For example, if the input signal is Vestigial Side Band (VSB) modulated, the demodulator 104 performs a VSB demodulation. On the other hand, if the input signal is Orthogonal Frequency Division Multiplexing (OFDM) modulated, the demodulator 104 performs all OFDM demodulation to output a demodulated signal to the demultiplexer 105.
The demodulated signal input to the demultiplexer 105 is a multiplexed transport packet including the audio signal, the video signal and the additional information data. Thus, the demultiplexer 105 demultiplexes the signal under the control of the controller 109 and separates the audio/video signals from the additional information data. The audio/video signals are output to the audio/video decoder 106 and the additional information including the program guide information such as the title, rating, time and plot of a program is stored in the storage 108.
The audio/video decoder 106 decodes the audio/video signals and outputs the decoded signal to the display unit 107. The display unit 107 displays the decoded video signals on a TV screen and plays the decoded audio signals through a speaker. The additional information data regarding a program being displayed on the display unit is read from the storage 108 by the controller 109 and temporarily stored in the memory 110. The controller 109 then informs users through the display unit 107 that there is additional information for the program being displayed. If there is a request to view the additional information from the user, the controller 109 reads the additional information data stored in the memory 110 and displays the information on the display unit 107.
Therefore, the digital TV as described above can display information regarding the program such as a program content, program time, names of heroes, if additional information is transmitted by broadcasting stations or external program providers. But, a user's request for more information cannot be met due to the limitation of the EPG data.